This invention relates generally to high pressure water jet cutting machines for both edging and bordering, and for forming circular openings and elongated slots in a workpiece. More specifically, the invention relates to such machines wherein bordering is accomplished by one or more water jet cutting tools separately carried on one or more monorail track mounted carriage assemblies and wherein aperture formation is accomplished by one or more cutting tools separately mounted on a like number of arms extending from a plate which is fixedly oriented in a horizontal plane, while circularly oscillating in such plane, or by one or more cutting tools eccentrically positioned on a like number of cams, wherein each cam is rotatably mounted on a different stationary arm.
Broadly speaking, high pressure water jet cutting machines, which employ one or more water jet cutting tools individually and separately mounted on a like number of computer controlled robotic arms for fashioning borders and for forming apertures in a workpiece, have long been known and used in the prior art. One difficulty that has been encountered using such a robotic arm carried water jet cutter results from the relatively large amount of operating space often required for placement and movement of the arm, especially when used for trimming edges or borders of a workpiece. Such large operating space requirements can often severely limit and even, in some cases, prevent the simultaneous use of two or more robotic arm cutters to reduce border cutting time, as well as aperture cutting time where several holes and/or slots are to be cut in a single workpiece. Such limitations arise due to the necessity of avoiding collisions between two or more simultaneously operating robotic arms.
Another difficulty that has been encountered using a robotic arm mounted water jet cutting tool is in the relatively large amount of time required to cut an individual hole in a workpiece. Typically, where a hole is to be cut in a foam material, such as urethane, for example, mechanical movement of the arm to the required operating position, plus activation and subsequent deactivation of a high pressure water valve connected to the water jet cutting nozzle on the arm, will take no less than 2.0 seconds to cut a single hole in the material. Furthermore, if space requirements do not permit the ganging of two or more robotic arm cutters to simultaneously cut two or more holes required in a workpiece, then, typically, it can take at least 2.0 seconds for one robotic arm cutter to cut each separate hole sequentially.
Still another difficulty encountered in using a computer controlled robotic arm carried water jet cutting tool is the relatively high cost of each such arm.
It, therefore, would be desirable to provide a water jet cutting machine which can cut both edges or borders and apertures in a workpiece, which completely eliminates the need for expensive robotic arms. It would also be desirable to provide such a machine which greatly improves the ability to gang water jet cutters for simultaneous operation, both in edge trimming and in cutting numerous apertures, holes and/or slots in a workpiece to reduce overall cutting time. It would further be desirable to provide such a machine that has the capability of reducing individual hole cutting time from the at least 2 seconds, as required by a robotic arm cutter, to no more than about 0.4 seconds.
By means of my invention, these and other difficulties encountered using prior art robotic arm carried water jet cutting tools are substantially eliminated.